The sound pressure level and found out, that this PSU has a good fan speed regulation. The RPMs are tolerable up to 50-80% load. Beyond that point, this PSU is no longer silent, but still quiet enough. Note the difference the power grid makes in terms of efficiency. 115VAC means higher current and more stress for all power supplies, while 230VAC shows a worse power factor at all loads. Nevertheless, 0.975 PFC is still good and most users will find 83% efficiency more than sufficient. All the rails fall clearly within ATX specifications.

I've got a Shuttle SZ77R5 with a 500W PSU, running an i7-3770k and a GeForce GTX 670... It doesn't get all that much faster than this without your cost/performance ratio going to crap, and the 500W PSU is way more than enough.

Why this is the case should be obvious: the processor has a 77W TDP, the graphics chip has a tdp of 170W, which is 247W at full load, and those are the two biggest power draws in the case. Yes, the other parts use power, like the hard disks (I've got SSDs), fans, memory, chipset, etc. but not enough to max out even a 500W PSU.Reply

For your system a 500W supply sounds great, but for other people they might have more stuff in their box that needs more power. For example, my main system has an i7-920, GTX 560, and 14hdds. It was giving me random fits occasionally when rebooting on my old 650W supply (can't remember the name but I believe it was one of the recommended ones either on here or tom's or someplace) I ended up replacing it with an 850W and now I don't get restart cycles anymore. Theoretically, the 650W supply had enough power to run everything (and still 100+W of spare capacity), but something wasn't happy and a large supply seems to have fixed everything.Reply

I think he's almost certainly correct in that the PSU was a problem -- HDDs tend to draw power differently than GPUs and CPUs (same voltage, different rails). The real question is what he's doing with 14 HDDs in a single system. Sounds more like something for a file server, and if you're running a file server you should probably also have a higher quality PSU to begin with.

As for your contention that he has an "American mentality towards the environment", kindly take your stereotyping elsewhere. Very likely this has nothing at all to do with his nationality and is simply a reflection of his enthusiasm for computers and technology.Reply

Hard drives are commonly designed to draw up to 2 amps on the 12 volt line when spinning up, so if you spin up 14 hard drives at ones the power draw could be 2A * 12V * 14 = 672 watts. Normally, systems with large numbers of hard drives are configured to spin up a few drives at a time to avoid overloading the power supply. The alternative is to do what you did: buy a very large power supply.Reply

Still running a Corsair 450W VX PSU since 2007 here. Currently with an overclocked Phenom II X4 system and GTX460. Rock solid. I always laugh when people ask whether their new 750W PSU's will be enough for a Sandy Bridge and Radeon 6850 plus one SSD...Reply

That's what I want to know. I use the same two all the time, but I am almost scared to find out how they actually test.

Most users do not notice, and do not care. They only want the cheapest PSU. I may get them to allow me to installed a better one, but only so far. Most of the PSU's reviewed here are marginal in that regard.

We're talking about systems with a core i3 and integrated graphics, and a single hard drive. Maybe it can push 100-120 watts, when the grand kids try to play WOW on their grandparents' computer. Sometimes they want the $25 model even.

Shoot, for office workstations I use these Cooler Masters even. I haven't had a problem yet. Nowadays that means Core-i5, 8GB DDR3, and 60GB SSD. I built a server recently that only used 18watts at idle! It is just hard to find good PSU's at less then 400 watts.Reply